Cappuccino type beverages exist which are formed of coffee topped with foamed milk. These beverages are relatively easy to produce in automatic dispensers by first foaming the milk and delivering the foam in the cup, then, providing the coffee liquid through the foam.
Layered Cappuccino type beverages, are more complex coffee specialties which can be found in coffee houses and mid to upscale restaurants. A typical beverage called “Latte Macchiato”, consists of two distinct layers of milk and espresso coffee topped with milk foam. Other recipes that can be found are “White Mocha” beverages made of a bottom layer of white chocolate with a top layer of espresso coffee or cocoa/coffee based beverages with a bottom layer of hot chocolate, espresso coffee intermediate layer and milk foam on top. Since all these beverages provide visual appeal to the consumers, they are generally served in transparent containers such as a glass. They are usually consumed in two ways; either by stirring the product, for example when sugar is added, or by drinking the beverage layer by layer.
The preparation of layered Cappuccino type beverages and the like is typically executed manually and, therefore, requires skilled personnel and very careful attention for proper preparation. Furthermore, the preparation is time consuming and requires more labor than for serving usual coffee or milk beverages. Furthermore, because of the by hand preparation, the consistency of the final product may vary from product to product and from operator to operator depending upon his/her skills and available preparation time. When preparing the so-called Lattee Macchiato or layered Cappuccino, the milk foam and espresso coffee are prepared separately. The glass is first filled with hot foamed milk. Some time is allowed to stabilize the foam, and finally espresso is slowly poured over the milk and foam, creating a layered effect as viewed through the serving glass. To reduce the preparation time and allow consumers to drink layered beverages at home or in the office, some automation has been introduced in coffee machines, but these do not provide truly automatic dispensing and some manual preparation or cleaning is required.
U.S. Pat. No. 6,220,147 entitled “Beverage preparation and layering device for an espresso machine” describes a layering tool, attached to the outlet tube adjacent to the lower end, to create a layered drink of two distinct substances. The layering device consists of a concave spoon attachment for an espresso machine. The spoon simulates the manual preparation of layered beverages. The spoon gently pours the second liquid on top of the first component to form a distinct layer. The concave tube attachment can be located within a beverage container with the spoon at the approximate layer of the first layer beverage. A disadvantage of this layering method is that it requires assembly prior to preparation of layered beverages and manual use by operators. Further, the device needs to be cleaned after dispensing because of contact with the beverages and should be removed whenever a non-layered beverage has to be delivered.
Another layering tool for pouring liquids as non-mixed layers is described in the Belgian patent BE 899988 (Herbots, 1984). The device consists of a dispensing opening connected to a float, vertically movable along it. The float has the shape of a platform so it can receive the downward fluid gently spreading the liquid on the respective surface levels. This device can work for cocktails, Irish coffee or other liquids with small differences in density. A disadvantage of this layering tool is that it also requires assembly prior to preparation of layered beverages and manual use by operators. Further, this device is not part of a coffee machine, and should manually be used when dispensing a layered drink.
Macco S.p.A., Franke Kaffeemachinen A G and Palux are currently manufacturing coffee machines that dispense various products including a layered beverage (Latte Macchiato) from coffee beans and refrigerated fresh milk. In the Bremer coffee machine, hot milk is first dispensed, followed by milk foam. Finally, steam-extracted coffee from fresh-ground beans is dispensed on top of the beverage. The delivery rate is 2.1 g/s.
A disadvantage of this method is that it takes relatively long time to dispense a layered beverage and it requires refrigerated milk. The method used in these coffee machines could not be used to prepare layered beverages from liquid concentrates because steam vapor is implemented to extract the coffee creating a liquid with density lower than diluted coffee concentrate. Further, the steam venturi system would not work with dense and viscous concentrates.
Therefore, there is no method and device existing for dispensing of layered beverages which are fast, convenient, automated and reproducible. The present invention now provides such a new method and device to generate both hot and cold layered beverages.